I've been thinking of downloading NRaas StoryProgression for awhile now but my main worry is if I install it do I need to restart my neighborhood and family or can I continue playing my existing family ?

Nope can continue playing your existing family. *Edit* Twallan has retired though and his mods are updated to 1.63 so if you are updated to 1.66 they may not work, I wouldn't know since I haven't been keeping up on if they work or not because I'm not planning on updating my game at all anymore. I know there was some talk of people continuing his work but thats about all I know.

That's good cause I just created my family and didn't want to redo them. I have 1.63 and won't be updating to 1.66 I only have the base game sofar.

Being worked on at NRaas and most are in testing now... here's a couple of links if you would like a status: http://nraas.wikispaces.com/News+Of+The+Day http://nraas.wikispaces.com/Update+History+Testing+166

When you first run your saved game after installing it you will get a pop-up asking if you want to enable NRAAS Story Progression. Once it's enabled, you will want to -immediately- pause the game and adjust the options for the stories it tells you about so you won't be flooded with popups about sims you don't care about.

I don't know of any Mods that would require you to restart a family. All the ones I've encountered can be added to the game at any time. (Someone correct me if I'm wrong.)

There's only two changes with Story Progession that I dislike, and the popups about everyone else's lives are one of them.

To change what Ghost Sdoj is talking about, click on City Hall -> NRass -> Story Progression -> General Options -> All Stories (I usually change it to Friends and Blood Relatives.)

I've been playing with it since last night and love it wish I would have downloaded when it came out.